Bump prometheus-client from 0.13.1 to 0.20.0

Bumps [prometheus-client](https://github.com/prometheus/client_python) from 0.13.1 to 0.20.0.
- [Release notes](https://github.com/prometheus/client_python/releases)
- [Commits](prometheus/client_python@v0.13.1...v0.20.0)

---
updated-dependencies:
- dependency-name: prometheus-client
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

pyproject.toml

@@ -70,7 +70,7 @@ rich = { version = "^12.5.1", optional = false }
 rich-click = { version = "^1.5.1", optional = false }
 
 # metrics
-prometheus-client = { version = "^0.13.1", optional = false }
+prometheus-client = { version = ">=0.13.1,<0.21.0", optional = false }
 
 # flask_architect
 flask = { version = "^1.1", optional = false }